This is a wall-mounted acoustic masking unit that protects the privacy of users at public toilets in stations, buildings, schools, hotels, and elsewhere. Japanese people have a habit of flushing toilets many times to mask noise. This product has contributed to water saving by making a loud flushing sound without emitting water. This new product also increases the masking effect by adjusting the frequency band to the toilet ambiance. Since many people use the toilet, the device is designed to be fully operated without touching. Set horizontally, it blends into the toilet space.